Body mass index, waist circumference, and risk of hearing loss: a meta-analysis and systematic review of observational study

BACKGROUND@#Emerging evidence implicates excess weight as a potential risk factor for hearing loss. However, this association remained inconclusive. Therefore, we aimed to systematically and quantitatively review the published observational study on the association between body mass index (BMI) or waist circumference (WC) and hearing loss.@*METHODS@#The odds ratios (ORs) or relative risks (RRs) with their 95% confidence intervals (CIs) were pooled under a random-effects model. Fourteen observational studies were eligible for the inclusion in the final analysis.@*RESULTS@#In the meta-analysis of cross-sectional studies, the ORs for prevalent hearing loss were 1.10 (95% CI 0.88, 1.38) underweight, 1.14 (95% CI 0.99, 1.32) for overweight, OR 1.40 (95% CI 1.14, 1.72) for obesity, 1.14 (95% CI 1.04, 1.24) for each 5 kg/m increase in BMI, and 1.22 (95% CO 0.88. 1.68) for higher WC. In the meta-analysis of longitudinal studies, the RRs were 0.96 (95% CI 0.52, 1.79) for underweight, 1.15 (95% CI 1.04, 1.27) for overweight, 1.38 (95% CI 1.07, 1.79) for obesity, 1.15 (95% CI 1.01, 1.30) for each 5 kg/m increase in BMI, and 1.11 (95% CI 1.01, 1.22) for higher WC.@*CONCLUSIONS@#In summary, our findings add weight to the evidence that elevated BMI and higher WC may be positively associated with the risk of hearing loss.

Role of Mediterranean diet in prevention and management of type 2 diabetes.

OBJECTIVE: To summarize the importance of Mediterranean diet in the prevention and management of type 2 diabetes. DATA SOURCES: We searched electronic database on PubMed up to 14 April 2014, we identified these articles with following key words: "Mediterranean diet" and "diabetes". The initial search resulted in 451 entries. The search strategy had no language and publication date restrictions. The relevance of the studies was assessed based only on the title and abstract. The studies included in our review had to match the following inclusion criteria: (1) randomized clinical trials and meta-analysis or systematic review, and (2) provided strong evidence for the diet as a way to prevent type 2 diabetes, and improve glycemic control and cardiovascular risk factors in diabetic patients. We reviewed 49 manuscripts and only 22 met our inclusion criteria. STUDY SELECTION: Relevant literatures including randomized control trials, meta-analysis or systematic review. RESULTS: Based on several studies, Mediterranean diet is inversely related to type 2 diabetes and plays important roles in the management of type 2 diabetes. Based on the evidence gathered and evaluated from various studies, we concluded combination and interaction of Mediterranean diet components, such as fruits, vegetables, nuts, legumes, whole grains, fish and moderate intakes of red wine, which contain essential nutrients and health promoting properties, including high fibers, high magnesium, high anti-oxidant and high monounsaturatal fatty acids (MUFA). Interaction and combination of these essential nutrients and health promoting properties found to lower body weight, hemoglobin A1C (HbA1c), low density lipoprotein (LDL), oxidative-stress and improve high density lipoprotein (HDL) level; which are beneficial for prevention and prognosis improvement of type 2 diabetes. CONCLUSIONS: In the modern society, poor dietary habits accompanied by inadequate physical activity are associated with the risk of having obesity and type 2 diabetes. Promoting healthy lifestyle and diet are not only beneficial in the prevention and treatment of various diseases but also important in maintaining the overall health. Switching from unhealthy diet to health-friendly diet such as Mediterranean diet represents healthy lifestyle choice.